(CNN) -- Eighty percent of baby boomers are pessimistic about the current direction of the United States, according to the Pew Research Center's Social & Demographic Trends study released Monday.

Who can blame them, with retirement and pension funds shrinking and with the unemployment rate near 10%?

The boomer generation consists of adults between the ages of 45 and 64, according to the The Pew Research Center, a nonpartisan think tank.

"Most Americans are pretty glum three years into a Great Recession and a jobless recovery, but even in that context, the baby boomers stand out," said Paul Taylor, co-author of the study and vice president of the center.

In contrast, the study found only 60% of millennials -- individuals between the ages of 18 and 29 -- had a bleak view of the way things are going today.

And about 76% of respondents older than baby boomers, also called the "greatest generation," were dissatisfied with the status quo.

The study says boomers have reported less overall life satisfaction during their adulthood than have previous generations. One-fifth of baby boomers believe their standard of living is lower than their parents'. And about a third expect their children to experience an even lower standard of living.

The grim results arrive before next month's milestone, when the oldest baby boomers will turn 65. America's baby boomer generation of 79 million people adds up to a little more than a quarter of the U.S. population, the center reports.

Over the next 19 years, about 10,000 people will turn 65 each day, the survey reports, resulting in a grayer America by 2030. By that year, 18% of the nation's population will be over the age of 65, compared with 13% now.

The Pew survey did not examine why the baby boomer generation has a gloomy outlook. Some believe it's a result of being middle-aged, a time when people experience more psychological stresses and demands. Others experts blame the lackluster economy.

Taylor said there were two other theories posed by outside experts. First, some experts blame challenges to baby boomers that other generations have not had to face. Because the boomer generation is so large, members have historically faced tremendous competition in the workplace from their peers.

"They had a tougher fight to get jobs and crawl up the ladder," he said.

Another theory is that the idealistic boomers experienced their prime during their youth in 1960s when they fought for civil and women's rights. Now, they may be finding they were unable to complete the societal reforms they had envisioned.

"They may have set themselves up for disappointment," Taylor said.

The Pew center also found data gathered from previous reports that offers boomers' views on social change, personal finance, economics and religion. Here is a summary:

• About 7 out of 10 boomers say the main purpose of marriage is mutual happiness and fulfillment, rather than raising a child. In comparison, only half of adults 65 and older believed that.

• When it comes to the idea of alternative lifestyles, boomers are less accepting of same-sex couples raising children and of unmarried couples cohabiting than the millennial generation.

• Boomers are more likely to accept divorce as a solution to marriage woes. About two-thirds of them say divorce is better than staying in an unhappy marriage, compared with 54 percent of younger adults.

• Among all the age groups, boomers are the most likely to say they lost money on investments since the recession began.

• Six out of 10 boomers between the ages of 50 and 61 say they may have to postpone retirement.

• The younger boomers, between the ages of 45 and 55, say they are nearly as likely to be online as younger adults.

• About 43 percent of boomers say they are a "strong" member of their religion, which represents a higher percentage than adults in younger generations.